/*
 * Copyright (C) 2005-2011 MaNGOS <http://www.getmangos.com/>
 *
 * Copyright (C) 2008-2011 Trinity <http://www.trinitycore.org/>
 *
 * Copyright (C) 2010-2011 ProjectSkyfire <http://www.projectskyfire.org/>
 * 
 * Copyright (C) 2011 ArkCORE <http://www.arkania.net/>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "gamePCH.h"
#include "CombatAI.h"
#include "SpellMgr.h"
#include "Vehicle.h"

int AggressorAI::Permissible(const Creature *creature) {
	// have some hostile factions, it will be selected by IsHostileTo check at MoveInLineOfSight
	if (!creature->isCivilian() && !creature->IsNeutralToAll())
		return PERMIT_BASE_PROACTIVE;

	return PERMIT_BASE_NO;
}

void AggressorAI::UpdateAI(const uint32 /*diff*/) {
	if (!UpdateVictim())
		return;

	DoMeleeAttackIfReady();
}

// some day we will delete these useless things
int CombatAI::Permissible(const Creature * /*creature*/) {
	return PERMIT_BASE_NO;
}

int ArchorAI::Permissible(const Creature * /*creature*/) {
	return PERMIT_BASE_NO;
}

int TurretAI::Permissible(const Creature * /*creature*/) {
	return PERMIT_BASE_NO;
}

int AOEAI::Permissible(const Creature * /*creature*/) {
	return PERMIT_BASE_NO;
}

int VehicleAI::Permissible(const Creature * /*creature*/) {
	return PERMIT_BASE_NO;
}

void CombatAI::InitializeAI() {
	for (uint32 i = 0; i < CREATURE_MAX_SPELLS; ++i)
		if (me->m_spells[i] && GetSpellStore()->LookupEntry(me->m_spells[i]))
			spells.push_back(me->m_spells[i]);

	CreatureAI::InitializeAI();
}

void CombatAI::Reset() {
	events.Reset();
}

void CombatAI::JustDied(Unit *killer) {
	for (SpellVct::iterator i = spells.begin(); i != spells.end(); ++i)
		if (AISpellInfo[*i].condition == AICOND_DIE)
			me->CastSpell(killer, *i, true);
}

void CombatAI::EnterCombat(Unit *who) {
	for (SpellVct::iterator i = spells.begin(); i != spells.end(); ++i) {
		if (AISpellInfo[*i].condition == AICOND_AGGRO)
			me->CastSpell(who, *i, false);
		else if (AISpellInfo[*i].condition == AICOND_COMBAT)
			events.ScheduleEvent(
					*i,
					AISpellInfo[*i].cooldown
							+ rand() % AISpellInfo[*i].cooldown);
	}
}

void CombatAI::UpdateAI(const uint32 diff) {
	if (!UpdateVictim())
		return;

	events.Update(diff);

	if (me->HasUnitState(UNIT_STAT_CASTING))
		return;

	if (uint32 spellId = events.ExecuteEvent()) {
		DoCast(spellId);
		events.ScheduleEvent(
				spellId,
				AISpellInfo[spellId].cooldown
						+ rand() % AISpellInfo[spellId].cooldown);
	} else
		DoMeleeAttackIfReady();
}

/////////////////
//CasterAI
/////////////////

void CasterAI::InitializeAI() {
	CombatAI::InitializeAI();

	float m_attackDist = 30.0f;
	for (SpellVct::iterator itr = spells.begin(); itr != spells.end(); ++itr)
		if (AISpellInfo[*itr].condition == AICOND_COMBAT
				&& m_attackDist > GetAISpellInfo(*itr)->maxRange)
			m_attackDist = GetAISpellInfo(*itr)->maxRange;
	if (m_attackDist == 30.0f)
		m_attackDist = MELEE_RANGE;
}

void CasterAI::EnterCombat(Unit *who) {
	if (spells.empty())
		return;

	uint32 spell = rand() % spells.size();
	uint32 count = 0;
	for (SpellVct::iterator itr = spells.begin(); itr != spells.end();
			++itr, ++count) {
		if (AISpellInfo[*itr].condition == AICOND_AGGRO)
			me->CastSpell(who, *itr, false);
		else if (AISpellInfo[*itr].condition == AICOND_COMBAT) {
			uint32 cooldown = GetAISpellInfo(*itr)->realCooldown;
			if (count == spell) {
				DoCast(spells[spell]);
				cooldown += me->GetCurrentSpellCastTime(*itr);
			}
			events.ScheduleEvent(*itr, cooldown);
		}
	}
}

void CasterAI::UpdateAI(const uint32 diff) {
	if (!UpdateVictim())
		return;

	events.Update(diff);

	if (me->HasUnitState(UNIT_STAT_CASTING))
		return;

	if (uint32 spellId = events.ExecuteEvent()) {
		DoCast(spellId);
		uint32 casttime = me->GetCurrentSpellCastTime(spellId);
		events.ScheduleEvent(
				spellId,
				(casttime ? casttime : 500)
						+ GetAISpellInfo(spellId)->realCooldown);
	}
}

//////////////
//ArchorAI
//////////////

ArchorAI::ArchorAI(Creature *c) :
		CreatureAI(c) {
	if (!me->m_spells[0])
		sLog->outError(
				"ArchorAI set for creature (entry = %u) with spell1=0. AI will do nothing",
				me->GetEntry());

	m_minRange = GetSpellMinRange(me->m_spells[0], false);
	if (!m_minRange)
		m_minRange = MELEE_RANGE;
	me->m_CombatDistance = GetSpellMaxRange(me->m_spells[0], false);
	me->m_SightDistance = me->m_CombatDistance;
}

void ArchorAI::AttackStart(Unit *who) {
	if (!who)
		return;

	if (me->IsWithinCombatRange(who, m_minRange)) {
		if (me->Attack(who, true) && !who->IsFlying())
			me->GetMotionMaster()->MoveChase(who);
	} else {
		if (me->Attack(who, false) && !who->IsFlying())
			me->GetMotionMaster()->MoveChase(who, me->m_CombatDistance);
	}

	if (who->IsFlying())
		me->GetMotionMaster()->MoveIdle();
}

void ArchorAI::UpdateAI(const uint32 /*diff*/) {
	if (!UpdateVictim())
		return;

	if (!me->IsWithinCombatRange(me->getVictim(), m_minRange))
		DoSpellAttackIfReady(me->m_spells[0]);
	else
		DoMeleeAttackIfReady();
}

//////////////
//TurretAI
//////////////

TurretAI::TurretAI(Creature *c) :
		CreatureAI(c) {
	if (!me->m_spells[0])
		sLog->outError(
				"TurretAI set for creature (entry = %u) with spell1=0. AI will do nothing",
				me->GetEntry());

	m_minRange = GetSpellMinRange(me->m_spells[0], false);
	me->m_CombatDistance = GetSpellMaxRange(me->m_spells[0], false);
	me->m_SightDistance = me->m_CombatDistance;
}

bool TurretAI::CanAIAttack(const Unit * /*who*/) const {
	// TODO: use one function to replace it
	if (!me->IsWithinCombatRange(me->getVictim(), me->m_CombatDistance)
			|| (m_minRange
					&& me->IsWithinCombatRange(me->getVictim(), m_minRange)))
		return false;
	return true;
}

void TurretAI::AttackStart(Unit *who) {
	if (who)
		me->Attack(who, false);
}

void TurretAI::UpdateAI(const uint32 /*diff*/) {
	if (!UpdateVictim())
		return;

	DoSpellAttackIfReady(me->m_spells[0]);
}

//////////////
//AOEAI
//////////////

AOEAI::AOEAI(Creature *c) :
		CreatureAI(c) {
	if (!me->m_spells[0])
		sLog->outError(
				"AOEAI set for creature (entry = %u) with spell1=0. AI will do nothing",
				me->GetEntry());

	me->SetVisible(true); //visible to see all spell anims
	me->SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_NOT_SELECTABLE); //can't be targeted
	me->SetFlag(UNIT_FIELD_FLAGS, UNIT_FLAG_NOT_ATTACKABLE_1); //can't be damaged
	me->SetDisplayId(11686); //invisible model, around a size of a player
}

bool AOEAI::CanAIAttack(const Unit * /*who*/) const {
	return false;
}

void AOEAI::AttackStart(Unit * /*who*/) {
}

void AOEAI::UpdateAI(const uint32 /*diff*/) {
	if (!me->HasAura(me->m_spells[0]))
		me->CastSpell(me, me->m_spells[0], false);
}

//////////////
//VehicleAI
//////////////

VehicleAI::VehicleAI(Creature *c) :
		CreatureAI(c), m_vehicle(c->GetVehicleKit()), m_IsVehicleInUse(false), m_ConditionsTimer(
				VEHICLE_CONDITION_CHECK_TIME) {
	LoadConditions();
	m_DoDismiss = false;
	m_DismissTimer = VEHICLE_DISMISS_TIME;
}

//NOTE: VehicleAI::UpdateAI runs even while the vehicle is mounted
void VehicleAI::UpdateAI(const uint32 diff) {
	CheckConditions(diff);

	if (m_DoDismiss) {
		if (m_DismissTimer < diff) {
			m_DoDismiss = false;
			me->SetVisible(false);
			me->ForcedDespawn();
		} else
			m_DismissTimer -= diff;
	}
}

void VehicleAI::Reset() {
	me->SetVisible(true);

	m_vehicle->Reset();
}

void VehicleAI::OnCharmed(bool apply) {
	if (m_IsVehicleInUse && !apply && !conditions.empty()) //was used and has conditions
			{
		m_DoDismiss = true; //needs reset
		me->RemoveFlag(UNIT_NPC_FLAGS, UNIT_NPC_FLAG_PLAYER_VEHICLE);
		me->RemoveFlag(UNIT_NPC_FLAGS, UNIT_NPC_FLAG_SPELLCLICK);
	} else if (apply)
		m_DoDismiss = false; //in use again
	m_DismissTimer = VEHICLE_DISMISS_TIME; //reset timer
	m_IsVehicleInUse = apply;
}

void VehicleAI::LoadConditions() {
	conditions = sConditionMgr->GetConditionsForNotGroupedEntry(
			CONDITION_SOURCE_TYPE_CREATURE_TEMPLATE_VEHICLE, me->GetEntry());
	if (!conditions.empty())
		sLog->outDebug(LOG_FILTER_CONDITIONSYS,
				"VehicleAI::LoadConditions: loaded %u conditions",
				uint32(conditions.size()));
}

void VehicleAI::CheckConditions(const uint32 diff) {
	if (m_ConditionsTimer < diff) {
		if (!conditions.empty()) {
			for (SeatMap::iterator itr = m_vehicle->m_Seats.begin();
					itr != m_vehicle->m_Seats.end(); ++itr)
				if (Unit *passenger = itr->second.passenger) {
					if (Player* plr = passenger->ToPlayer()) {
						if (!sConditionMgr->IsPlayerMeetToConditions(plr,
								conditions)) {
							plr->ExitVehicle();
							return; //check other pessanger in next tick
						}
					}
				}
		}
		m_ConditionsTimer = VEHICLE_CONDITION_CHECK_TIME;
	} else
		m_ConditionsTimer -= diff;
}
